Peter wrote:
> >$ref =
> > sub{my%k;@k{@{+pop}}=\(@_);splice@_,$_,!$k{$_}for reverse
> > 0..@_;\@_}->(@A,\@I);
>
> Oh, well, if I'd known it was *that* succinct...
>
> But... that *does* involve copying; the original poster was talking
> about huge arrays where copying was actually significant. You've
> got the list of keys and values in the temporary hash there. It
> certainly violates the spirit of the request.
Picky, picky, picky. Very well, here's a version that involves absolutely
no copying of elements or indices...
-----------cut-----------cut-----------cut-----------cut-----------cut----------
@A = (1..10); # array
sub sliceref
{my($i,$o,$k)=(0,0,pop);$i+$o-$k->[$i]?++$o&&splice@_,$i,1:$i++while$i<@_;\@_}
my $ref = sliceref @A, [3..5,9]; # reference to slice
print "@A\n";
print "@$ref\n";
$ref->[1] = 99;
print "@A\n";
print "@$ref\n";
-----------cut-----------cut-----------cut-----------cut-----------cut----------
> Which still seems like a reasonable request.
I'd agree.
> A reference to a slice in perl 5 yields the list of the references
> to the slice members. Is that the way it's going to be in perl 6?
I would suspect so, since a slice is a list, not an array.
But, of course, that wouldn't preclude a different syntax for generating
a cross-sectional view of an array.
Damian
